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    <title>Document</title>
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        h1 {
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            background: brown;
            opacity: 50%;
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        .qinjiang {
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            font-size: 1cm;
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        #id {
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    <h1 id="id">2333</h1>
    <h1 id="2">2333</h1>
    <p class="qinjiang">大叔大婶多
    </p>
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